(Carbamoyl)pyridino derivatives of ureidocephalosporins

ABSTRACT

Ureido cephalosporin derivatives of the formula ##STR1## wherein R 1  is hydrogen or methoxy; R 2  is hydrogen or lower alkyl; R 3  is hydrogen, lower alkyl, cycloalkyl, cycloalkenyl, cycloalkadienyl, phenyl, phenyl-lower alkyl, substituted phenyl, substituted phenyl-lower alkyl; or certain heterocyclic groups; are disclosed. These compounds are useful as antibacterial agents.

BACKGROUND OF THE INVENTION

Cephalosporins having a carbamoyl substituted pyridinomethyl group inthe 3-position are disclosed in U.S. Pat. Nos. including 3,261,832;3,449,338; 3,479,350; 3,483,197; 3,557,104; 3,632,810; etc; and GermanOffenlegungsschrift No. 2,234,280.

Cephalosporins having a ureido acyl side chain are disclosed in U.S.Pat. Nos. 3,673,183; 3,708,479; 3,833,568; and 3,860,591. Cephalosporinshaving various acyl side chains and a 7α-methoxy substituent are taughtin various U.S. Pat. Nos. including 3,775,410; 3,780,031; 3,780,033;3,780,034; 3,780,037; 3,843,641; etc.

Cephalosporins having an acylureido acyl side chain are disclosed inU.S. Pat. Nos. 3,687,949 and 3,925,368 and German OffenlegungsschriftNos. 2,513,954 and 2,514,019.

SUMMARY OF THE INVENTION

This invention relates to new carbamoyl substituted pyridinomethylureidocephalosporins of the formula ##STR2## R₁ represents hydrogen ormethoxy. The R₁ substituent is in the α-configuration as indicated bythe broken lines (.tbd.).

R₂ represents hydrogen or lower alkyl.

R₃ represents hydrogen, lower alkyl, cycloalkyl, cycloalkenyl,cycloalkadienyl, phenyl, phenyl-lower alkyl, substituted phenyl,substituted phenyl-lower alkyl, or certain heterocyclic groups.

DETAILED DESCRIPTION OF THE INVENTION

The various groups represented by the symbols have the meaning definedbelow and these definitions are retained throughout this specification.

The lower alkyl groups referred to throughout this specification includestraight or branched chain hydrocarbon groups containing 1 to 8 carbonatoms, preferably 1 to 4 carbons. Examples of the type of groupscontemplated are methyl, ethyl, propyl, isopropyl, butyl, t-butyl, etc.The lower alkoxy groups include such lower alkyl groups attached to anoxygen, e.g., methoxy, ethoxy, propoxy, etc. The phenyllower alkylgroups include such lower alkyl groups attached to a phenyl, preferablybenzyl and phenethyl.

Cycloalkyl refers to groups having 3 to 7 carbons in the ring, i.e.cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and cycloheptyl. Theterm cycloalkenyl also represent rings having 3 to 7 carbon atoms withone double bond, i.e. cyclobutenyl, cyclopentenyl, cyclohexenyl, etc.The term cycloalkadienyl represents a ring having 6 or 7 carbons withtwo double bonds located at various positions such as1,4-cyclohexadienyl which is preferred.

The substituted phenyl and substituted phenyl-lower alkyl groups includeone or two substituents selected from halogen (preferably chlorine orbromine), lower alkyl of 1 to 4 carbons (preferably methyl or ethyl),lower alkoxy of 1 to 4 carbons (preferably methoxy or ethoxy), andhydroxy, e.g. 2-, 3-, or 4-chlorophenyl, 2-, 3-, or 4-bromobenzyl, 2-,3-, or 4-hydroxyphenyl, 3,5-dichlorophenyl, 2-, 3-, or 4-methylphenyl,2-, 3-, or 4-ethoxyphenyl, etc.

The heterocyclic groups represented by R₃ are 2-thienyl, 3-thienyl,2-furyl, 3-furyl, 2-pyridyl, 3-pyridyl, or 4-pyridyl. Also includedwithin the meaning of R₃ are such heterocyclics having a halogen(preferably Cl or Br) or a lower alkyl of 1-4 carbons (preferably methylor ethyl) substituent, i.e. 2-(4-chlorothienyl), 3-(4-methylthienyl),etc.

The compounds of formula I can be prepared by several methods. Thepreferred method is by reacting a compound of the formula ##STR3## orits sodium salt with a carbamoyl substituted pyridine in a polar solventsuch as water and in the presence of a catalyst such as an alkali metalthiocyanate.

The compounds of formula II can be obtained by acylating an α-ureidocompound of the formula ##STR4## with a 7-ACA or 7α-methoxy-7-ACA of theformula ##STR5## wherein R is preferably diphenylmethyl or another esterprotecting group. The resulting product is then treated to remove theester group such as by the use of anisole and trifluoroacetic acid toyield the compound of formula II.

In this reaction, the α-ureido compound of formula III must first beconverted into an activated form. For example, the α-ureido compound offormula III can be converted to a mixed carbonic or other anhydride bytreating a solution of the α-ureido compound in an organic solventcontaining a tri(lower alkyl)amine with an anhydride forming agent, i.e.a lower alkyl chloroformate, an aryl chloroformate, or an acyl halide,at reduced temperatures of from about 0° C to about -20° C.Alternatively, the α-ureido compound of formula III can be converted toan activated eser by reacting with a carboxyl group activating agentsuch as dicyclohexylcarbodiimide or bisimidazole carbonyl. In some casesthe carboxyl group may be activated by conversion to an acid halide,e.g. the chloride, or to an azide. The methods of preparing the α-ureidocompounds of formula III are known to those skilled in the art and anumber of such methods are discussed in U.S. Pat. Nos. 3,673,183 and3,833,568 referred to above.

Alternatively, the compounds of formula I can also be obtained byreacting an α-amino intermediate of the formula ##STR6## preferably inthe form of its trifluoroacetic acid salt with an isocyanate of theformula

    R.sub.2 --N=C=O                                            (VI)

wherein R₂ is hydrogen, lower alkyl or an alkali or alkaline earth saltsuch as potassium. Also, the intermediate of formula V can be reactedwith a compound of the formula ##STR7## wherein R₂ is as defined aboveand halo is Cl or Br.

The α-amino intermediate of formula V can be obtained by various methodssuch as by acylating the compound of formula IV with a substitutedα-amino acid of the formula ##STR8## wherein Y is a protecting groupsuch as ##STR9## The α-amino protecting group is then removed bytreating the resulting cephalosporin with trifluoroacetic acid andanisole.

Alternatively, the final compounds of formula I can be obtained byreacting the intermediate of formula V with a carbamoyl substitutedpyridine followed by reaction with a compound of formula VI, VII, orVIII.

Also, the final compounds of formula I can be obtained by reacting thestarting material of formula IV with a carbamoyl substituted pyridinefollowed by an acylation reaction with an activated form of the α-ureidocompound of formula III.

It will be appreciated that the compounds of formula I are opticallyactive due to the presence of an asymmetric carbon atom represented asC^(*) in the preceding formulas. By selection of the appropriatestarting material it is possible to obtain the compounds of formula I asa mixture of optically active isomers or isolated as a single isomer.The various isomers as well as their mixtures are within the scope ofthis invention.

Preferred compounds of this invention are those of formula I wherein R₃is cyclohexenyl, cyclohexadienyl, phenyl, benzyl, phenethyl, substitutedphenyl, benzyl, or phenethyl wherein the substituent is on the phenylring and is one or two members selected from chloro, bromo, methyl,ethyl, methoxy, ethoxy and hydroxy, or a substituted or unsubstitutedheterocyclic selected from 2-thienyl, 3-thienyl, 2-furyl, 3-furyl,2-pyridyl, 3-pyridyl and 4-pyridyl wherein the heterocyclic substituentis chloro, bromo, methyl, or ethyl and R₂ is hydrogen or straight orbranched chain alkyl of 1 to 4 carbons.

The most preferred final compounds are those of formula I wherein thecarbamoyl substituent is the 4-position and R₄ is 2-thienyl, 3-thienyl,phenyl, or 4-hydroxyphenyl.

The compounds of formula I have a broad spectrum of antibacterialactivity against both gram positive and gram negative organisms such asStaphylococcus aureus, Salmonella schottmuelleri, Pseudomonasaeruginosa, Proteus rettgeri, Escherichia coli, Klebsiella pneumoniae,Serratia marcescens, etc. They may be used as antibacterial agents in aprophylactic manner, e.g., in cleaning or as surface disinfectingcompositions, or otherwise to combat infections due to organisms such asthose named above, and in general may be utilized in a manner similar tocephalothin and other cephalosporins. For example, a compound of formulaI or a physiologically acceptable salt thereof may be used in variousanimal species in an amount of about 1 to 100 mg./kg., daily, orally, orparenterally, in single or two to four divided to treat infections ofbacterial origin, e.g., 5.0 mg./kg. in mice.

Up to about 600 mg. of an acid compound of formula I of aphysiologically acceptable salt thereof may be incorporated in an oraldosage form such as tablets, capsules or elixirs or in an injectableform in a sterile aqueous vehicle prepared according to conventionalpharmaceutical practice.

They may also be used in cleaning or disinfecting compositions, e.g.,for cleaning barns or dairy equipment, at a concentration of about 0.2to 1% by weight of such compounds admixed with, suspended or dissolvedin cnventional inert dry or aqueous carriers for application by washingor spraying.

They are also useful as nutritional supplements in animal feeds.

Illustrative process details are provided in the examples for thevarious reactions. All temperatures are on the centigrade scale.

EXAMPLE 1 7β-[[D-[(Aminocarbonyl)amino]-2-thienylacetyl]amino]-3-[[4-(aminocarbonyl)pyridino]methyl]-8-oxo-5-thia-1-azabicyclo-[4.2.0]oct-2-ene-2-carboxylicacid a.D-2-[[[(4-Methoxyphenyl)methoxy]carbonyl]amino]-2-thiopheneacetic acid

74 g. of D-2-Thienylglycine are dissolved in 940 ml. of water. 37.8 g.of magnesium oxide are added and to this resulting suspension a solutionof 107.5 g. of p-methoxybenzyloxycarbonylazide in 940 ml. of dioxane isadded with stirring. The mixture is stirred at room temperature for 24hours It is then filtered and the filtrate is extracted with 600 ml. ofether. The extract is discarded. The water in dioxane phase is layeredover with 600 ml. of ethyl acetate, cooled to 5° and brought to pH 2with 2N hydrochloric acid. The layers are separated and the aqueouslayer is again extracted with 300 ml. of ethyl acetate. The combinedethyl acetate extracts are washed with water, dried with magnesiumsulfate, filtered and concentrated. The oily residue crystallizes upontrituration with petroleum ether to yield 118 g. ofD-2-[[[(4-methoxyphenyl)methoxy]carbonyl]amino]-2-thiopheneacetic acid;m.p. 84°-94°; [α]₂₀ ^(D) : -69° (c=1, tetrahydrofuran).

b.3-[(Acetyloxy)methyl]-7β-[[D-[[[(4-methoxyphenyl)methoxy]-carbonyl]amino]-2-thienylacetyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid

3.2 g. (0.01 mole) of theD-2-[[[(4-methoxyphenyl)-methoxy]carbonyl]amino]-2-thiophenacetic acidfrom part (a) are brought into solution in 40 ml. of methylene chloridewith 1.1 ml. of N-methylmorpholine. The solution is cooled to -15°, 1.39ml. of isobutylchloroformate are added, and the mixture is stirred for10 minutes. To this is added a solution of 3.26 g. (0.1012 mol.) of7-aminocephalosporanic acid and 3.1 ml. of triethylamine in 40 ml. ofmethylene chloride. The mixture is stirred for 1 hour at -5° and 1 hourat 5°. This mixture is then evaporated to dryness in a rotaryevaporator. The solid residue is triturated with ether and filteredunder suction. The substance is then dissolved in ice water, layeredover with ethyl acetate and acidified to pH 2.5. The layers areseparated, the aqueous layer is extracted once more with ethyl acetate,the combined ethyl acetate extracts are washed with water, dried withmagnesium sulfate and concentrated. The residue (4.9 g.) is dissolved in200 ml. of ethyl acetate and the solution is treated with activatedcarbon. After filtration, 2 g. of 3-[(acetyloxy)methyl]-7β-[[D-[[[(4-methoxyphenyl)methoxy]carbonyl]amino]-2-thienylacetyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid, crystallize; m.p. 142°-143° (dec.).

c.3-[(Acetyloxy)methyl]-7β-[D-2-amino-2-(2-thienyl)acetamido]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid

2.0 g. of the product from part (b) are added at -5° to a mixture of 10ml. of trifluoroacetic acid and 4 ml. of anisole. The mixture is stirredfor 15 minutes and is then concentrated in a rotary evaporator. Theresidue is treated with ether and filtered under suction. The crude3-[(acetyloxy)-methyl]-7β-[D-2-amino-2-(2-thienyl)acetamido]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid, trifluoroacetic acid salt is dissolved in 50 ml. of water and 20ml. of a solution of the acetate form of the ion exchange resinAmberlite LA 1 in isobutylmethyl ketone are added. The mixture isstirred for 2 hours at room temperature. The layers are separated, theaqueous phase is washed several times with ether and freeze-dried toyield3-[(acetyloxy)methyl]-7β-[D-2-amino-2-(2-thienyl)acetamido]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid.

d.3-[(Acetyloxy)methyl]-7β-[[D-[(aminocarbonyl)amino]-2-thienylactyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]-oct-2-ene-2-carboxylicacid, sodium salt

A mixture of 1 g. of the product from part (c) and 0.194 g. of potassiumcyanate in 7.5 ml. of water are quickly heated in a preheated bath at80°. The mixture is then immediately cooled to room temperature andpermitted to stand overnight. The reaction mixture is concentrated toabout 4 ml. and the pH is adjusted to 1.5 with 2N hydrochloric acid. Theprecipitate is filtered under suction to obtain3-[(acetyloxy)methyl]-7β-[[D-[(aminocarbonyl)amino]-2-thienylacetyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid.

An aqueous equimolar mixture of this acid and sodium bicarbonate islyophilized to yield3-[(acetyloxy)methyl]-7β-[[D-[(aminocarbonyl)amino]-2-thienylactyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid, sodium salt.

e.7β-[[D-[(Aminocarbonyl)amino]-2-thienylacetyl]amino-3-[[4-(aminocarbonyl)pyridino]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid

A mixture of 2.38 g. (0.005 mole) of the sodium salt product from part(d), 0.915 (0.0075 mole) of 4-pyridinecarboxamide, 12 g. of potassiumthiocyanate and 7.5 ml. of water is heated at 50° for 24 hours. A clearsolution is obtained.

A chromatography column is filled with 150 g. of ion exchange resinAmberlite XAD-2. An additional 150 g. are made into a paste with alittle water and added to the above reaction solution. This solution isstirred for 30 minutes and then added to the chromatography columncontaining the 150 g. of resin. The column is eluted with 30 ml.portions of water. After 120 fractions which are discarded, the columnis eluted with a mixture of water and methanol (80:20) and fractions of10 ml. each are collected. Fractions 47-120 are concentrated to about150 ml. and freeze-dried. The residue is triturated with ether to obtain0.7 g. of7β-[[D-[(aminocarbonyl)amino]-2-thienylactyl]amino]-3-[[4-(aminocarbonyl)pyridino]methyl]-8-oxo-5-thia-1-azabicyclo-[4.2.0]oct-2-ene-2-carboxylicacid; m.p. 160°-165° (dec.).

In an analogous manner, by employing L-2-thienylglycine for the D-isomerin part (a), one obtains7β-[[L-[(aminocarbonyl)amino]-2-thienylacetyl]amino]-3-[[4-(aminocarbonyl)pyridino]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]-oct-2-ene-2-carboxylicacid.

EXAMPLE 27α-Methoxy-7β-[[D-[(aminocarbonyl)amino]-2-thienylacetyl]-amino]-3-[[4-(aminocarbonyl)pyridino]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid a.3-[(Acetyloxy)methyl]-7α-methoxy-7α-[[D-[[[(4-methoxyphenyl)-methoxy]carbonyl]amino]-2-thienylacetyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid, diphenylmethyl ester

3.2 g. (0.01 mol.) of the product from example 1(a) is brought intosolution in 40 ml. of methylene chloride with 1.1 ml ofN-methylmorpholine. The solution is cooled to -15°, 1.39 ml. ofisobutylchloroformate are added, and the mixture is stirred for 10minutes. To this is added a solution of 4.7 g. (0.01 mol.) of7β-amino-7-α-methoxy cephalosporanic acid diphenylmethyl ester and 3.1ml. of triethylamine in 40 ml. of methylene chloride. The mixture isstirred for 1 hour at -5° and 1 hour at 5°. This mixture is thenevaporated to dryness in a rotary evaporator and the solid residue istriturated with ether and filtered under suction to yield the titledcompound.

b.3-[(Acetyloxy)methyl]-7α-methoxy-7β-[D-2-amino-2-(2-thienyl)-acetamido]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid

The product from part (a) is treated with trifluoroacetic acid andanisole according to the procedure of example 1(c) to yield3-[(acetyloxy)methyl]-7α-methoxy-7β-[D-2-amino-2-(2-thienyl)-acetamido]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid.

c.3-[(Acetyloxy)methyl]-7α-methoxy-7β-[[D-[(aminocarbonyl)-amino]-2-thienylacetyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid, sodium salt

The product from part (b) is reacted with potassium cyanate according tothe procedure of example 1(d) to yield3-[(acetyloxy)methyl]-7α-methoxy-7β-[[D-[(aminocarbonyl)amino]-2-thienylacetyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid.

An aqueous equimolar solution of this acid and sodium bicarbonate islyophilized to yield3-[(acetyloxy)methyl]7α-methoxy-7β-[[D-[(aminocarbonyl)amino]-2-thienylacetyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid, sodium salt.

d.7α-Methoxy-7β-[[D-[(aminocarbonyl)amino]-2-thienylacetyl]-amino]-3-[[4-(aminocarbonyl)pyridino]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid

The sodium salt from part (c), 4-pyridinecarboxamide, potassiumthiocyanate and water are reacted according to the procedure of example1(e) to yield7α-methoxy-7β-[[D-[(aminocarbonyl)amino]-2-thienylacetyl]amino]-3-[[4(aminocarbonyl)-pyridino]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid.

In an analogous manner, one can obtain7α-methoxy-7β-[[L-[(aminocarbonyl)amino]-2thienylacetyl]amino]-3-[[4-[aminocarbonyl]pyridino]methyl]-8-oxo-5thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid.

EXAMPLE 37β-[[D-[(Aminocarbonyl)amino]phenylacetyl]amino]-3-[[4-(aminocarbonyl)pyridino]-methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid, hydrate a.D-2-[[[(4-Methoxyphenyl)methoxy]carbonyl]amino]phenylacetic acid

D-Phenylglycine and magnesium oxide are suspended in water and reactedwith p-methoxybenzyloxcarbonylazide according to the procedure ofexample 1 (a) to yieldD-2-[[[(4-methoxyphenyl)-methoxy]carbonyl]amino]phenylacetic acid.

b.3-[(Acetyloxy)methyl]-7β-[D-2-amino-2-phenylacetamido]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-carboxylicacid

The product from pat (a) and 7-aminocephalosporanic acid are reactedaccording to the procedure of example 1 (b) to yield3-[(acetyloxy)methyl]-7β-[[D-[[[(4-methoxyphenyl)-methoxy]carbonyl]amino]phenylacetyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid.

This compound is then treated with trifluoroacetic acid and anisoleaccording to the proceudre of example 1 (c) to yield3-[(acetyloxy)methyl]-7β-[D-2-amino-2-phenylacetamido]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid.

c.3-[(Acetyloxy)methyl]-7β-[[D-[(aminocarbonyl)amino]phenylacetyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid, sodium salt

The product from part (b) is reacted with potassium cyanate according tothe procedure of example 1 (d) to yield3-[(acetyloxy)methyl]-7β-[[D-[(aminocarbonyl)amino]phenylacetyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid.

An aqueous equimolar solution of this acid and sodium bicarbonate islyophilized to yield the sodium salt.

d.7β-[[D-[(Aminocarbonyl)amino]phenylacetyl]amino]-3-[[4-(aminocarbonyl)pyridino]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid, hydrate

A mixture of 1.88 g. (0.004 mole) of the sodium salt product from part(c), 0.732 g. (0.006 mole) of 4-pyridinecarboxamide, 9.6 g. of potassiumthiocyanate and 6 ml. of water is heated at 150° for 24 hours. A clearsolution is obtained. A chromatography column is filled with 70 g. ofion exchange resin Amberlite XAD-2. The reaction solution is dilutedwith 30 ml. of water and is admixed with 200 g. of a paste of ionexchange resin Amberlite XAD-2-. This mixture is stirred for 30 minutesand added to the chromatography column containing the 70 g. of ionexchange resin. The column is then eluted with 30 ml. portions of water.After 120 fractions are collected, the column is eluted with a mixtureof water and methanol (80:20) and 10 ml. fractions are collected. Theeluate is subjected to thin layer chromatography and checked for thecontent of the desired product. Fractions 45-120 of the watermethanoleluate are combined and concentrated to about 150 ml. to yield ascrystals 160 mg. of7β-[[D-8(aminocarbonyl)amino]phenylacetyl]-3-[[4-(aminocarbonyl)pyridino]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid, hydrate; m.p. 187°-190° (dec.). An additional 280 mg. of not sopure material are obtained from the mother liquor. Fractions 121-160 ofthe water-methanol eluate are concentrated to about 50 ml. andlyophilized to obtain an additional 100 mg. of the desired product; m.p.177°-185° (dec.).

In an analogous manner, by employing L-phenylglycine in part (a), oneobtains7β-[[L-[(aminocarbonyl)amino]phenylacetyl]amino]-3-[[4-(aminocarbonyl]pyridino]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid, hydrate.

EXAMPLES 4-25

Following the procedure of examples 1-3 but employing the acylatingagent shown in Col. I and the 7α-methoxy ordesmethoxy-7β-amino-cephalosporanic acid (or its diphenylmethyl ester)shown in Col. II one obtains the intermediate of Col. III (or itsdiphenylmethyl ester). The protecting group (and ester group) areremoved by treatment with trifluoroacetic acid and anisole. Treatment ofthe resulting trifluoroacetic acid salt with potassium cyanate yieldsthe acid of Col. IV. The acid of Col. IV in converted to its sodium saltand reacted with the carbamoyl substituted pyridine of Col. V to yieldthe final product of Col. VI. ##STR10##

    ______________________________________                                         Ex  R.sub.3           R.sub.1                                                ______________________________________                                         4                                                                                 ##STR11##        H        4                                               5                                                                                 ##STR12##        H        3                                               6                                                                                 ##STR13##        OCH.sub.3                                                                              4                                               7                                                                                 ##STR14##        H        2                                               8                                                                                 ##STR15##        OCH.sub.3                                                                              4                                               9                                                                                 ##STR16##        H        4                                              10                                                                                 ##STR17##        OCH.sub.3                                                                              3                                              11                                                                                 ##STR18##        H        2                                              12                                                                                 ##STR19##        OCH.sub.3                                                                              4                                              13                                                                                 ##STR20##        H        4                                              14                                                                                 ##STR21##        OCH.sub.3                                                                              4                                              15                                                                                 ##STR22##        H        2                                              16                                                                                 ##STR23##        OCH.sub.3                                                                              4                                              17                                                                                 ##STR24##        H        4                                              18                                                                                 ##STR25##        H        3                                              19                                                                                 ##STR26##        H        4                                              20                                                                                 ##STR27##        OCH.sub.3                                                                              4                                              21                                                                                 ##STR28##        H        3                                              22                                                                                 ##STR29##        OCH.sub.3                                                                              4                                              23  H                 H        4                                              24  C.sub.2 H.sub.5   OCH.sub.3                                                                              4                                              25                                                                                 ##STR30##        H        4                                              ______________________________________                                    

The acylating agents of Col. I may be in either the D- or L- form or maybe a mixture of D- and L- isomers.

EXAMPLE 267β-[D-[(Methylaminocarbonyl)amino]-2-thienylacetyl]amino]-3-[[4-(aminocarbonyl)pyridino]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid a.3-[(Acetyloxy)methyl]-7β-[[D-[(methylaminocarbonyl)amino]-2-thienylacetyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid, sodium salt

1.5 g. of3-[(acetyloxy)methyl]-7β-[D-2-amino-2-(2-thienyl)acetamido]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid, trifluoroacetic acid salt from example 1(c) and 1.01 ml. oftriethylamine are dissolved at 0°-5° in 20 ml. of anhydrous methylenechloride. To the clear solution is added 2.49 g. of a 10% solution ofmethylisocyanate in methylene chloride. This mixture is stirred for 2hours at 0°-5° and then concentrated. The residue is taken up in alittle water, shaken with ether, filtered and acidified with 2Nhydrochloric acid to yield3-[(acetyloxy)methyl]-7β-[[D-[(methylaminocarbonyl)amino]-2-thienylacetyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid.

An aqueous equimolar solution of this acid and sodium bicarbonate islyophilized to yield3-[(acetyloxy)methyl]-7β-[[D-[(methylaminocarbonyl)amino]-2-thienylacetyl]amino]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid, sodium salt.

b.7β-[[D-[(Methylaminocarbonyl)amino]-2-thienylacetyl]amino]-3-[[4-(aminocarbonyl)pyridino]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid

The sodium salt product from part (a) is reacted with4-pyridinecarboxamide, potassium thiocyanate and water according to theprocedure of example 1(e) to yield7β-[[D-[(methylaminocarbonyl)amino]-2-thienylacetyl]amino]-3-[[4-(aminocarbonyl)pyridino]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid.

In an analogous manner, one can obtain7β-[[L-[(methylaminocarbonyl)amino]-2-thienylacetyl]amino]-3-[[4-(aminocarbonyl)pyridino]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid.

EXAMPLES 27-33

Following the procedure of example 26 but substituting for themethylisocyanate one of the following:

ethylisocyanate

n-propylisocyanate

i-propylisocyanate

n-butylisocyanate

i-butylisocyanate

t-butylisocyanate

n-pentylisocyanate

one obtains:

7β-[[D-[(ethylaminocarbonyl)amino]-2-thienylacetyl]amino]-3-[[4-(aminocarbonyl)pyridino]methyl]-8-oxo-5-thia-1-azabicyclo[2.4.0]oct-2-ene-2-carboxylicacid;

7β-[[D-[(n-propylaminocarbonyl)amino]-2-thienylacetyl]amino]-3-[[4-(aminocarbonyl)pyridino]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid;

7β-[[D-[(i-propylaminocarbonyl)amino]-2-thienylacetyl]amino]-3-[[4-(aminocarbonyl)pyridino]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid;

7β-[[D-[(n-butylaminocarbonyl)amino]-2-thienylacetyl]amino]-3-[[4-(aminocarbonyl)pyridino]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]octo-2-ene-2-carboxylicacid;

7β-[[D-[(i-butylaminocarbonyl)amino]-2-thienylacetyl]amino]-3-[[4-(aminocarbonyl)pyridino]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid;

7β-[[D-[(t-butylaminocarbonyl)amino]-2-thienylacetyl]amino]-3-[[4-(aminocarbonyl)pyridino]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid; and

7β-[[D-[(n-pentylaminocarbonyl)amino]-2-thienylacetyl]amino]-3-[[4-(aminocarbonyl)pyridino]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid; respectively.

In an analogous manner, one can obtain the L-isomers of the compounds ofexamples 27 to 33.

Similarly, by employing the methylisocyanate from example 26 or thealkylisocyanates of examples 27-33 in the procedure of examples 2 to 25,other compounds within the scope of this invention are obtained.

What is claimed is:
 1. A compound of the formula ##STR31## wherein R₂ ishydrogen or lower alkyl; R₃ is phenyl, phenyl-lower alkyl, substitutedphenyl or phenyl-lower alkyl wherein said phenyl substituent is one ortwo members selected from the group consisting of halogen, lower alkylof 1 to 4 carbons, lower alkoxy of 1 to 4 carbons, and hydroxy, or asubstituted or unsubstituted heterocyclic selected from the groupconsisting of 2-thienyl, 3-thienyl, 2-furyl, and 3-furyl, where saidheterocyclic substituent is attached to an available carbon atom and ishalogen or lower alkyl of 1 to 4 carbons; and the ##STR32## substituentis in 2-, or 3- or 4-position.
 2. The compound of claim 1 wherein R₂ ishydrogen or straight or branched chain alkyl of 1 to 8 carbons; and R₃is phenyl, benzyl, phenethyl, substituted phenyl, benzyl or phenethylwherein said substituent is on the phenyl ring and is one or two membersselected from the group consisting of chloro, bromo, methyl, ethyl,methoxy, ethoxy and hydroxy, or a substituted or unsubstitutedheterocyclic selected from the group consisting of 2-thienyl, 3-thienyl,2-furyl, and 3-furyl, wherein said heterocyclic substituent is attachedat an available carbon atom and is chloro, bromo, methyl, or ethyl. 3.The compound of claim 2 wherein R₂ is hydrogen.
 4. The compound of claim3 wherein R₃ is 2-thienyl, 3-thienyl, phenyl or 4-hydroxyphenyl; and the##STR33## substituent is in the 4-position.
 5. The compound of claim 4wherein R₃ is 2-thienyl.
 6. The compound of claim 5,7β-[[D-[(aminocarbonyl)amino]-2-thienylacetyl]amino]-3-[[4-(aminocarbonyl)pyridino]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid.
 7. The compound of claim 6,7β-[[L-[(aminocarbonyl)amino]-2-thienylacetyl]amino]-3-[[4-(aminocarbonyl)pyridino]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid.
 8. The compound of claim 4 wherein R₃ is phenyl.
 9. The compoundof claim 8,7β-[[D-[(aminocarbonyl)amino]phenylacetyl]amino]-3-[[4-(aminocarbonyl)pyridino]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid.
 10. The compound of claim 9,7β-[[L-[(aminocarbonyl)amino]phenylacetyl]amino]-3-[[4-(aminocarbonyl)pyridino]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid.
 11. The compound of claim 4 wherein R₃ is 3-thienyl.
 12. Thecompound of claim 4 wherein R₃ is 4-hydroxyphenyl.
 13. The compound ofclaim 2 wherein R₂ is straight or branched chain alkyl of 1 to 8carbons.
 14. The compound of claim 13 wherein R₂ is straight or branchedchain alkyl of 1 to 4 carbons; R₃ is 2-thienyl, 3-thienyl, phenyl or4-hydroxyphenyl; and the ##STR34## substituent is in the 4-position. 15.The compound of claim 14 wherein R₃ is 2-thienyl.
 16. The compound ofclaim 15 wherein R₂ is methyl.
 17. The compound of claim 14 wherein R₃is 3-thienyl.
 18. The compound of claim 17 wherein R₂ is methyl.
 19. Thecompound of claim 14 wherein R₃ is phenyl.
 20. The compound of claim 19wherein R₂ is methyl.
 21. The compound of claim 14 wherein R₃ is4-hydroxyphenyl.
 22. The compound of claim 21 wherein R₂ is methyl.